Shackle for marine purposes.



No. 765,513. PATBNTED JULY 19, 1904.

. J. A. ROCK.

SHAGKLBPOR MARINE PURPOSES.

n APPLICATION FILED NOV. 11, 1903. NO MODEL.

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I UNITED STATES Patented July 19, 1904.

PATENT OFFICE.

SHACKLE FOR MARINE PURPOSES.

SPECIFICATION forming part 0f Letters Patent NO. '7 65,513, dated. July19, 1904:. Application filed November 11,1903. Serial No. 180,667. (Nomodel.)

To a/ZZ wtfmt it may con/007%:

Be it known that I, J AsrER ANDREW ROCK, a citizen of the United States,residing at San Francisco, in the county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements inShackles for Marine and other Purposes, of which the following is aspecification.

My invention relates to improvements in shackles such as are used onships, on derricks, and on other like apparatus.

Shackles as at present constructed are a constant source of expense byreason of their quickly wearing out. The shackles on board of a vesselare subjected to continuous wear without interruption from the time whenthe vessel leaves port until its return thereto. Each movement of thevessel causes the hook which engages the shackle to move backward andforward thereon, and as the vessel is never still during the voyage itwill readily be seen that the wear on the shackle on this account isvery great. Thus the expense of renewing these shackles is considerable,averaging about fifty dollars on a four months voyage of an ordinaryschooner. Besides, the great wear upon the shackles requires constantvigilance on the part of the oiiicers of the ship to assure themselvesthat the shackles are not worn through, the result of which latter eventwould be almost certain disaster, involving, perhaps, loss of life.

rIhe object of my invention is to provide a shackle which will last`much longer than those heretofore used without the expense being muchgreater. I have herein shown the improvement as applied to a ships gear;but the invention is also valuable in hoisting apparatus or wherevershackles are used.

My invention therefore resides in the novel construction, combination,and arrangement of parts for the above ends hereinafter fully specified,and particularly pointed out in the claim.

In the accompanying drawings, Figure l is a view of a ships sail,showing two forms of my invention applied thereto. Fig. 2 is an enlargedtop plan view of one form of my invention. Fig. 3 is a view, partly insection, of the same. Fig. 4 is an enlarged section of the same, showingthe means for oiling.

Referring to the drawings, l represents a ships sail, and 2 the mast. Tothe gaff 3 of said sail is secured the rope 4, attached by a block 5 anda hook 6 to the shackle 7, secured to the mast by an iron band aroundthe mast. This shackle is circular in form, and within said shackle is agrooved sheave or roller 9. Said sheave has a square central hole 10,through which is passed a square bolt 11, upon the ends of said boltbeing secured the arms 13 of a forked hanger 14, the lower end of s aidhanger having an eye 15, into which may be passed the hook 6.

By the above construction the wear of the block instead of being upon asingle point of the shackle at one time is distributed throughout halfthe circumference of the grooved roller. Thus the wear at each point isgreatly reduced. The central aperture and bolt are made square in orderto insure that' the bolt does not turn within the roller, which wouldcause a rapi'd wearupon the bolt.

In order to reduce the friction and wear, the bolt is made with an axialoil-channel 17, which terminates in a lateral channel 18, communicatingwith a radial channel 19, leading to the periphery of the roller. Bythis means after iilling up said channel with oil the oil will graduallyfind its way to the surface of the roller and will reduce frictionbetween said roller and shackle.

I claim- A shackle comprising a square bolt, a grooved sheave or rollerhaving asquare central aperture through which said bolt is passed aforked hanger through which the arms of said bolt passes, said hangerhaving at its other end an eye for a hook .and a shackle properconsisting of a bar extending around the roller for the greater part ofits circumference and in said groove, the Yends of said bar being thenextended parallel to but spaced from each other, and a tie-bar passingthrough said ends, substantially as described.

In witness whereof I have hereunto set my hand in the presence of twosubscribingwitnesses.

' J. A. ROCK. Witnesses:

FRANCIS M. WRIGHT, BEssIE GORFINKEL.

